Lua: load text module as `pandoc.text`.

This only affects the name in the Lua-internal documentation. It is
still possible to load the modules via `require 'text'`, although this
is deprecated.

5 files changed, 114 insertions, 3 deletions

diff --git a/pandoc-lua-engine/pandoc-lua-engine.cabal b/pandoc-lua-engine/pandoc-lua-engine.cabal
index 35cfde763..7501eae9e 100644
--- a/pandoc-lua-engine/pandoc-lua-engine.cabal
+++ b/pandoc-lua-engine/pandoc-lua-engine.cabal
@@ -88,6 +88,7 @@ library
                      , Text.Pandoc.Lua.Module.Structure
                      , Text.Pandoc.Lua.Module.System
                      , Text.Pandoc.Lua.Module.Template
+                     , Text.Pandoc.Lua.Module.Text
                      , Text.Pandoc.Lua.Module.Types
                      , Text.Pandoc.Lua.Module.Utils
                      , Text.Pandoc.Lua.Orphans
diff --git a/pandoc-lua-engine/src/Text/Pandoc/Lua/Init.hs b/pandoc-lua-engine/src/Text/Pandoc/Lua/Init.hs
index f41206bdc..60d39670a 100644
--- a/pandoc-lua-engine/src/Text/Pandoc/Lua/Init.hs
+++ b/pandoc-lua-engine/src/Text/Pandoc/Lua/Init.hs
@@ -35,7 +35,6 @@ import qualified Lua.LPeg as LPeg
 import qualified HsLua.Aeson
 import qualified HsLua.Module.DocLayout as Module.Layout
 import qualified HsLua.Module.Path as Module.Path
-import qualified HsLua.Module.Text as Module.Text
 import qualified HsLua.Module.Zip as Module.Zip
 import qualified Text.Pandoc.Lua.Module.CLI as Pandoc.CLI
 import qualified Text.Pandoc.Lua.Module.Format as Pandoc.Format
@@ -46,6 +45,7 @@ import qualified Text.Pandoc.Lua.Module.Scaffolding as Pandoc.Scaffolding
 import qualified Text.Pandoc.Lua.Module.Structure as Pandoc.Structure
 import qualified Text.Pandoc.Lua.Module.System as Pandoc.System
 import qualified Text.Pandoc.Lua.Module.Template as Pandoc.Template
+import qualified Text.Pandoc.Lua.Module.Text as Pandoc.Text
 import qualified Text.Pandoc.Lua.Module.Types as Pandoc.Types
 import qualified Text.Pandoc.Lua.Module.Utils as Pandoc.Utils
 
@@ -93,14 +93,13 @@ loadedModules =
   , Pandoc.Structure.documentedModule
   , Pandoc.System.documentedModule
   , Pandoc.Template.documentedModule
+  , Pandoc.Text.documentedModule
   , Pandoc.Types.documentedModule
   , Pandoc.Utils.documentedModule
   , Module.Layout.documentedModule { moduleName = "pandoc.layout" }
     `allSince` [2,18]
   , Module.Path.documentedModule { moduleName = "pandoc.path" }
     `allSince` [2,12]
-  , Module.Text.documentedModule
-    `allSince` [2,0,3]
   , Module.Zip.documentedModule { moduleName = "pandoc.zip" }
     `allSince` [3,0]
   ]
@@ -126,6 +125,13 @@ initLuaState = do
     -- load modules and add them to the `pandoc` module table.
     forM_ loadedModules $ \mdl -> do
       registerModule mdl
+      -- pandoc.text must be require-able as 'text' for backwards compat.
+      when (moduleName mdl == "pandoc.text") $ do
+        getfield registryindex loaded
+        pushvalue (nth  2)
+        setfield (nth 2) "text"
+        pop 1 -- _LOADED
+      -- Shorten name, drop everything before the first dot (if any).
       let fieldname (Name mdlname) = Name .
             maybe mdlname snd . Char8.uncons . snd $
             Char8.break (== '.') mdlname
diff --git a/pandoc-lua-engine/src/Text/Pandoc/Lua/Module/Text.hs b/pandoc-lua-engine/src/Text/Pandoc/Lua/Module/Text.hs
new file mode 100644
index 000000000..6705a5f62
--- /dev/null
+++ b/pandoc-lua-engine/src/Text/Pandoc/Lua/Module/Text.hs
@@ -0,0 +1,51 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-|
+Module      : Text.Pandoc.Lua.Module.Text
+Copyright   : © 2023 Albert Krewinkel
+License     : MIT
+Maintainer  : Albert Krewinkel <[email protected]>
+
+Lua module to work with UTF-8 strings.
+-}
+module Text.Pandoc.Lua.Module.Text
+  ( documentedModule
+  ) where
+
+import Data.Version (makeVersion)
+import HsLua
+import Text.Pandoc.Error (PandocError)
+import Text.Pandoc.Lua.PandocLua ()
+
+import qualified Data.Text as T
+import qualified HsLua.Module.Text as TM
+
+-- | The @aeson@ module specification.
+documentedModule :: Module PandocError
+documentedModule = TM.documentedModule
+  { moduleName = "pandoc.text"
+  , moduleFunctions =
+    [ TM.fromencoding `since` v[3,0]
+    , TM.len          `since` v[2,0,3]
+    , TM.lower        `since` v[2,0,3]
+    , TM.reverse      `since` v[2,0,3]
+    , TM.sub          `since` v[2,0,3]
+    , TM.toencoding   `since` v[3,0]
+    , TM.upper        `since` v[2,0,3]
+    ]
+  , moduleDescription = T.unlines
+    [ "UTF-8 aware text manipulation functions, implemented in Haskell."
+    , ""
+    , "The text module can also be loaded under the name `text`, although"
+    , "this is discouraged and deprecated."
+    , ""
+    , "``` lua"
+    , "-- uppercase all regular text in a document:"
+    , "function Str (s)"
+    , "  s.text = pandoc.text.upper(s.text)"
+    , "  return s"
+    , "end"
+    , "```"
+    ]
+  }
+ where
+  v = makeVersion
diff --git a/pandoc-lua-engine/test/Tests/Lua/Module.hs b/pandoc-lua-engine/test/Tests/Lua/Module.hs
index 08a4343d7..e3556f2cd 100644
--- a/pandoc-lua-engine/test/Tests/Lua/Module.hs
+++ b/pandoc-lua-engine/test/Tests/Lua/Module.hs
@@ -35,6 +35,8 @@ tests =
                   ("lua" </> "module" </> "pandoc-structure.lua")
   , testPandocLua "pandoc.template"
                   ("lua" </> "module" </> "pandoc-template.lua")
+  , testPandocLua "pandoc.text"
+                  ("lua" </> "module" </> "pandoc-text.lua")
   , testPandocLua "pandoc.types"
                   ("lua" </> "module" </> "pandoc-types.lua")
   , testPandocLua "pandoc.utils"
diff --git a/pandoc-lua-engine/test/lua/module/pandoc-text.lua b/pandoc-lua-engine/test/lua/module/pandoc-text.lua
new file mode 100644
index 000000000..71a06c917
--- /dev/null
+++ b/pandoc-lua-engine/test/lua/module/pandoc-text.lua
@@ -0,0 +1,51 @@
+--
+-- Tests for the pandoc.text module
+--
+local text = require 'pandoc.text'
+local tasty = require 'tasty'
+
+local group = tasty.test_group
+local test = tasty.test_case
+local assert = tasty.assert
+
+assert.is_function = function (x)
+  assert.are_equal(type(x), 'function')
+end
+-- We rely mostly on the tests in the `hslua-module-text` module. The
+-- only thing we need to test is whether `pandoc.text` is available,
+-- whether all functions are defined, and whether `require 'text'` works
+-- (for backwards compatibility).
+return {
+  group 'module' {
+    test('is table', function ()
+      assert.are_equal(type(text), 'table')
+    end),
+    test('can be required as "text"', function ()
+      assert.are_equal(require 'text', require 'pandoc.text')
+    end)
+  },
+
+  group 'functions' {
+    test('fromencoding', function ()
+      assert.is_function(text.fromencoding)
+    end),
+    test('len', function ()
+      assert.is_function(text.len)
+    end),
+    test('lower', function ()
+      assert.is_function(text.lower)
+    end),
+    test('reverse', function ()
+      assert.is_function(text.reverse)
+    end),
+    test('sub', function ()
+      assert.is_function(text.sub)
+    end),
+    test('toencoding', function ()
+      assert.is_function(text.toencoding)
+    end),
+    test('upper', function ()
+      assert.is_function(text.upper)
+    end),
+  },
+}